M2.3 earthquake 43 km ENE of Warm River, Idaho

A magnitude 2.3 earthquake struck 43 km ENE of Warm River, Idaho on Wed, Sep 8, 2021, 11:18 AM MDT (17:18 UTC), 5 km (3 mi) below the surface.

A larger quake followed: M3.0 44 km ENE of Warm River, Idaho. This one was a foreshock.

Map

Where this earthquake was located, with the others nearby. Select one for its page.

Different scales measure different things and differ by a few tenths. The USGS marks one as preferred, and it is the one this page uses.

Mag.	Scale	Computed by	Notes
2.28	Md, duration	University of Utah Seismograph Stations	Preferred · Final · ±0.386 · 3 stations
2.1	ML, local (Richter)	USGS National Earthquake Information Center	Reviewed · ±0.097 · 14 stations

1 person reported to the USGS what they felt; the strongest reported shaking was II, weak shaking.

Reviewed by a seismologist.

Distance and direction from each place to the epicenter, with its forecast.

Within 100 km, magnitude 1.5 and up: 70 in the 60 days after this one and 17 in the 30 days before it.

The first 60 of 70.

From the USGS Earthquake Hazards Program and its partner networks, event uu60028709 (also filed as us7000f9fm). Read Sun, Oct 4, 2026, 12:41 PM UTC.